Printing by lithography.



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JAMES BAY, OF JOUR-DANTOWN, TEXAS.

PRINTING BY LI'IHOG-RAPHY.

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No Drawing.

- producing engravings which have become worn or difiicult of working; furthermore, an object of this invention is to improve on the ordinary process of transferring by making it possible to transfer but one impression and make it into an engraving with but slight loss of effect.

' A further object of this invention is to provide means for printing by lithography in which the surface constituting the engraving is so treated as to produce more effective results and in which the engraving or stone can be prepared expeditiously and inexpensively as compared with known methods. I

In carrying the invention into practlce, an impression is made on lithographic transfer paper of a drawing that is to be engraved and it is then transferred to a lithographic stone and treated as an ord1- nary transfer until it can be rolled with a stiff ink to make it as clear as possible. The surface is then dusted with powdered asphaltum and etched with a weak solution of nitric acid and water. The stone is then washed with clean water and rubbed dry with a cloth. The design is then rubbed with textile material, preferably cotton havirig soap stone on it, the application of the soap stone to the lithographic stone serving to remove all sediment from the stone. The treated surface is then subjected to the action of a flame such as is produced by a spirit lamp until the asphaltum is melted after which the stone is permitted to cool and the design thereof is covered with a thin varnish composed of shellac three parts, dragons blood one fourth part, alcohol sixteen parts. When the surface thus treated is dry, it is rolled with a lithographic hand roller until it has a dark appearance. After the last mentioned step, a solution composed of oxalic acid one part, cream of tartar one-half part, acetic acid Specification of Letters Patent.

Patented Mar. 2, 1915..

Application filed September 3, 1914. Serial No. 860,067.

' one-fourth part, is applied to the surface and the said surface is then rubbed with a piece of cotton until the design appears as a negative. The design is then rolled with a hand roller and transfer ink is applied as is customary in practice. The surface of the stone is then prepared with rosin and etched about one minute with a solution consisting of nitric acid one-fourth part, water thirty-two parts. The stone is then rolled as before and dusted with rosin as before. The design is then etched to the depth required with a compound consisting of acetic acid one part, water one part. The stone is then washed with clear water and rubbed dry, and covered with a thin coating of tusch. When the stone as thus treated has become dry, it should be washed with turpentine and a thin solution of asphaltum should be poured over the design. When the asphaltum has become dry, the whole stone should be washed with a solution consisting of potash two parts, tannic acid onefourth part, liquid gum arabic sixteen parts, alcohol sixteen parts, water sixteen parts. The solution consisting of the ingredients in the proportions stated will clean the stone of shellac and dragons blood and leave a clear design. The stone can then be gummed as for any lithographic engraving and when dry the dauber can be employed to spread the ink and the printing can be done.

Iclaim The process for lithographing engraving I consisting of impressing lithographic paper with a drawing to be engraved and transferring the same to a lithographic stone treated as an ordinary transfer until it can be rolled with stiff ink, in dusting the inked surface with powdered asphaltum, in etching the said surface, washing the surface with clear water, drying the same, applying soap stone to the said surface, in melting the asphaltum contained on the surface, covering the design with a varnish, then rolling the said surface with a hand roller until it has a dark appearance, applying a solution of oxalic acid, cream of tartar and acetic acid to the said surface until the design appears as a negative, inrolling the said design with a hand roller and transfer ink, powdering the surface with a composition of rosin and in etching the said surface, in dusting the said surface with rosin and further etching the said surface with an acid,

in subjecting. the surface. to a coating of In testimony whereof, I hereunto aifix my tusch, Washing the Whole stone Withturpensignature in the presence of two Witnesses. tine and applying a liquid asphaltum over JAMES RAY the design and Washing the said asphaltum surface With a solution of potash, tannic Witnesses:

acid, gum arabic, alcohol and Water substan- J. C. CROUCH,

tially in the proportions "stated. W. P. GRAIN.

Copies of this patent may be ohtained for fiv e cents each, by addressing the Commissioner of Patents.

Washington, D. 0. 

